THE DELICATE BALANCE OF
ECOSYSTEMS
Lab 9
1.- Ecosystems are communities of
organisms interacting with a
particular environment. Invasive
species can throw off the delicate
balance of an ecosystem, destroying
several species in the process. We are
going to simulate the give-and-take of
an imaginary ecosystem and observe
what happens when the “delicate
balance” of this ecosystem is corrupted.
2- A very simplified food chain is
diagrammed below, which will serve as
the basis for our simulation.
eats
predator
→ native herbivore
producer
invasive herbivore
General rules for this simulation:
I.- Every generation, the number of
producer doubles. Assume that the
plant population has enough sunlight,
carbon dioxide, and water to produce
new organisms.
II.- Every generation, each native herbivore
eats one plant to survive. Two native
herbivores produce one new offspring
each generation if they both consume
one plant.
(cont)
III.- Every generation, each predator must
consume two native herbivores in order
to survive into the next generation.
The predators are capable of surviving
for many generations.
(cont)
IV.- Once an invasive herbivore enters the
ecosystem, it is able to consume plants
before the native herbivores can. The
invaders each eat one plant every
generation. Two invasive herbivores
producer two new offspring each
generation if they each have consumed
one plant.
V.- The invasive herbivores have no natural
predators.
Procedure:
• Have someone from your group cut out
the playing pieces in your lab book.
You need only one set of pieces (from
one student’s lab). Lay all of the cut out
pieces out on your lab table.